A man activated his distress beacon after breaking down at sea, however the distress signal went undetected and he was only discovered when a vessel happened to pass by.
Modern 406MHz beacons replaced 121.5 MHz distress beacons in 2009, when they were phased out.
The older style beacons are no longer detected by satellite and can only be detected by nearby aircraft if they happen to be tuned into the frequency.
Australian Maritime Safety Authority Search and Rescue Operations Manager Al Lloyd said people should never rely on an obsolete beacon in an emergency.
“If people are in grave or imminent danger 121.5 beacons are unlikely to result in a search and rescue operation,” Mr Lloyd said.
“In this case AMSA and other authorities had no idea that this man was in distress and it’s extremely fortunate a passing boat that lead to a rescue.
“There could have been a very different outcome.”
The beacons have not been sold in Australia for more than six years. As well as being obsolete they are also likely to have expired batteries which may prevent them from activating at all.
AMSA urges anyone who still owns an old 121.5 MHz beacon to dispose of it appropriately and upgrade to a GPS enabled 406 MHz beacon.
The obsolete 121.5 MHz beacons cannot be registered with AMSA.
AMSA Search and Rescue relies on the registration details to gain vital information in the event of an emergency.
“If your beacon is registered, you can provide your vehicle or vessel details, your destination, how many people you have with you and nominate emergency contacts,” Mr Lloyd said.
“This gives search and rescue officers vital information to assist in any search and rescue operation.
“It can also lead to a faster response and rescue, and prevent unnecessary searches in the event of an accidental activation.”
This is the second incident involving an obsolete 121.5Mhz beacon this week, with another man rescued from a broken down boat in South Australia on Monday.
The man was fortunate a highflying aircraft detected the signal and AMSA was able to send a rescue helicopter to the location near Backstairs Passage off the South Australian coast.
The beacon was not detected by satellite.
For more information or to register your beacon for free visit www.amsa.gov.au/beacons.
I... with Search and Rescue experts on the dangers of having obsolete beacons may be available on request.